This post was written by Keith Dawson for UBM Tech’s community Web site All LED Lighting, sponsored by Philips Lumileds. It is archived here because the All LED Lighting site has gone dark. This material is Copyright 2013-2015 by UBM Americas.

2013-10-23

'Li-Fi' LED Bulb Claim From China

Chinese scientists say they have developed an LED light bulb with integral electronics that can transmit data at 150 Mbit/s. Include us among the Westerners who remain skeptical that this is news.

Last week, the Xinhua news agency reported on "successful experiments by Chinese scientists" that held out hope for the "country's netizens getting online through signals sent by lightbulbs (Li-Fi), instead of Wi-Fi." The research team was led by Chi Nan, an IT professor with Fudan University in Shanghai, and included scientists from the Shanghai Institute of Technical Physics of the Chinese Academy of Sciences. Xinhua did not include any photos or video of the purported bulb. We should have more details Nov. 5, when the researchers will show it off at the China International Industry Fair in Shanghai.

We've talked about the Li-Fi idea a couple of times. Xinhua acknowledges what we reported about the term's origins: It was coined in 2011 by Harald Haas of the University of Edinburgh.

Haas demonstrated streaming video over Li-Fi to the world in a TED talk in April 2011. He has since formed a Scottish company, pureVLC, to commercialize the technology. (The VLC stands for visible light communications). The University of Strathclyde in the UK has established an Intelligent Lighting Center for the same purpose. Experiments in Germany have demonstrated the possibility of achieving data rates of 3 Gbit/s from Li-Fi.

Getting it wrong
The Xinhua article makes much of the fact that 150 Mbit/s is faster than the Internet connections of most Chinese people. The implication is that somehow this technology could provide an infrastructure upgrade to the whole country. That is nonsense. Around the world, many people's WiFi connections at home are faster than the data pipes to their ISPs. I'm sorry, but faster local networks in homes do not equate to faster Internet service. Even the GigaOM reporter, who should know better, got this wrong.

Another thing GigaOM fluffed: The reporter assumed the Chinese technology could be delivered in the form of kits that magically convert LED light bulbs into Li-Fi data servers. (China has replaced more light bulbs with LEDs than North America has.) Xinhua did not claim the Li-Fi electronics were outboard from the light bulb; the article said the microchips were "embedded." I don't see how an outboard controller would work. So if this technology is commercialized, people are going to be replacing their new, long-life LED bulbs with newer ones that speak Li-Fi.

There's nothing new or revolutionary in the announcement out of Shanghai. The researchers there haven't done anything that Western scientists didn't demonstrate in a lab setting one or two years ago. There's nothing to see here; move along.